1. Field of the Invention
The present invention relates to isolated polypeptides having lipase activity and isolated polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods for producing and using the polypeptides.
2. Description of the Related Art
Triacylglycerol hydrolyzing enzymes are enzymes that catalyze the hydrolysis or formation of triglycerides. Triacylglycerol hydrolyzing enzymes are a versatile group of enzymes and often have more than one activity such as lipase, phospholipase, lysophospholipase, cholesterol esterase, cutinase, amidase, galactolipase, and other esterase type of activities. Which activity is the predominant activity will depend on the application of the enzyme and the conditions.
Triacylglycerol hydrolyzing enzymes belong to the IUBMB Enzyme Nomenclature 3.1.1. EC 3 refers to hydrolases, EC 3.1 refers to acting on ester bonds, and EC 3.1.1 refers to carboxylic ester hydrolases. Related enzymes are classified in EC 3.1.4, which refers to phosphoric diester hydrolases.
Lipases (EC 3.1.1.3) are enzymes that catalyze the hydrolysis of a wide range of carboxy esters, e.g., triglycerides to release fatty acid. Esterases (EC 3.1.1.1) are enzymes that catalyze the hydrolysis of water-soluble carboxylic esters, including short-chain fatty acid triglycerides, to produce an alcohol and a carboxylic acid anion.
Some lipases also have phospholipase activity and/or galactolipase activity (see, for example, U.S. Pat. No. 6,103,505 and U.S. Pat. No. 6,852,346), and can also have sterol esterase activity. (3.1.1.13).
Phospholipases are enzymes that catalyze the hydrolysis of phospholipids which consist of a glycerol backbone with two fatty acids in the sn1 and sn2 positions, which is esterified with a phosphoric acid in the sn3 position. The phosphoric acid may, in turn, be esterified to an amino alcohol.
There are several types of phospholipases which catalyze the hydrolysis of the fatty acyl moieties. These phospholipases include phospholipase A1 (EC 3.1.1.32), phospholipase A2 (EC 3.1.1.4), and lysophospholipase (EC 3.1.1.5). Phospholipase C (EC 3.1.4.3) and phospholipase D (EC 3.1.4.4) hydrolyze the phosphoric acid group from a phospholipid, but do not hydrolyze fatty acids like phospholipase A1, phospholipase A2 and phospholipase B.
Phospholipase A1 (EC 3.1.1.32) catalyzes the deacylation of one fatty acyl group in the sn1 position from a diacylglycerophospholipid to produce lysophospholipid and fatty acid. Phospholipase A2 (EC 3.1.1.4) catalyzes the deacylation of one fatty acyl group in the sn2 position from a diacylglycerophospholipid to produce lysophospholipid and fatty acid. Lysophospholipase (EC 3.1.1.5), also known as phospholipase B, catalyzes the hydrolysis of the fatty acyl group in a lysophospholipid. Phospholipase C (EC 3.1.4.3) catalyzes the hydrolysis of phosphatidylcholine to 1,2-diacylglycerol and choline phosphate. Phospholipase D (EC 3.1.4.4) catalyzes the hydrolysis of the terminal phosphate diester bond of phosphatidylcholine to produce choline and phosphatidic acid.
Galactolipases (EC 3.1.1.26) catalyze the hydrolysis of galactolipids by removing one or two fatty acids.
Sterol esterases (3.1.1.13) catalyze the hydrolysis of sterol esters to sterol and fatty acid.
Detergents formulated with lipolytic enzymes are known to have improved properties for removing fatty stains. For example, LIPOLASE™ (Novozymes A/S, Bagsvrd, Denmark), a microbial lipase obtained from the fungus Thermomyces lanuginosus (also called Humicola lanuginosa), has been introduced into many commercial brands of detergent. Lipases have also been used in degumming processes and baking.
El-Shahed et al., 1988, Egypt. J. Microbiol. 23: 537-547 and Mohawed et al., 1988, Egypt. J. Microbiol. 23: 357-372 disclose two Aspergillus fumigatus lipases. WO 03/12071 discloses a gene encoding a lipase from Aspergillus fumigatus. 
Mayordomo et al., 2000, J. Agric. Chem. 48: 105-109 disclose the isolation, purification, and characterization of a cold-active lipase from Aspergillus nidulans. 
Kundu et al., 1987, Journal of General Microbiology 133: 149-154, disclose the isolation and characterization of an extracellular lipase from the conidia of Neurospora crassa. 
Lipases have many commercial uses but very few lipases that work under application conditions and can be produced with high yields by microbial fermentation have been identified. There is a need in the art for alternative lipases with improved properties.
It is an object of the present invention to provide polypeptides having lipase activity and polynucleotides encoding the polypeptides.